In recent years, several high speed serial data communication standards, such as PCIe and Ethernet, have defined a set of initiating sequences between nodes on a data channel to optimize a maximum speed of communication over the data channel. These initiation or training sequences have a defined protocol with a definite starting point but a widely variable duration, which is largely dependent on the amount of attenuation in the serial channel. For 100 Gbps Ethernet, the training sequence can range in duration from 200 ms to 500 ms. Users have a desire to be able to determine the results of a final action in the training sequence, e.g. to determine the final results of the agreed protocol, but there is no present way to directly capture such results.
Despite the very long data record lengths used in present oscilloscopes, when initiating high speed data channels, the scope is often unable to fully capture the complete training sequence. Even if the data acquisition memory in the scope could store a long enough record to capture the entire training sequence, the amount of time required to process such a large record is many minutes, and would negatively impact the throughput of the instrument. Therefore, a software search for the final sequence also does not satisfy needs of the users, due to the long delay in processing such a long record.
Embodiments of the invention address these and other limitations of the prior art.